/*
  * Chronomaster DFA Format Demuxer
  * Copyright (c) 2011 Konstantin Shishkov
  *

  * This file is part of FFmpeg.

  *

  * FFmpeg is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *

  * FFmpeg is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public

  * License along with FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "libavutil/intreadwrite.h"
 #include "avformat.h"
 
 static int dfa_probe(AVProbeData *p)
 {
     if (p->buf_size < 4 || AV_RL32(p->buf) != MKTAG('D', 'F', 'I', 'A'))
         return 0;
 
     return AVPROBE_SCORE_MAX;
 }
 
 static int dfa_read_header(AVFormatContext *s,
                            AVFormatParameters *ap)
 {
     AVIOContext *pb = s->pb;
     AVStream *st;
     int frames;
     uint32_t mspf;
 
     if (avio_rl32(pb) != MKTAG('D', 'F', 'I', 'A')) {
         av_log(s, AV_LOG_ERROR, "Invalid magic for DFA\n");
         return AVERROR_INVALIDDATA;
     }
     avio_skip(pb, 2); // unused
     frames = avio_rl16(pb);
 
     st = av_new_stream(s, 0);
     if (!st)
         return AVERROR(ENOMEM);
 
     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
     st->codec->codec_id   = CODEC_ID_DFA;
     st->codec->width      = avio_rl16(pb);
     st->codec->height     = avio_rl16(pb);
     mspf = avio_rl32(pb);
     if (!mspf) {
         av_log(s, AV_LOG_WARNING, "Zero FPS reported, defaulting to 10\n");
         mspf = 100;
     }
     av_set_pts_info(st, 24, mspf, 1000);
     avio_skip(pb, 128 - 16); // padding
     st->duration = frames;
 
     return 0;
 }
 
 static int dfa_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     AVIOContext *pb = s->pb;
     uint32_t frame_size;
     int ret, first = 1;
 
     if (pb->eof_reached)
         return AVERROR_EOF;
 
     if (av_get_packet(pb, pkt, 12) != 12)
         return AVERROR(EIO);
     while (!pb->eof_reached) {
         if (!first) {
             ret = av_append_packet(pb, pkt, 12);
             if (ret < 0) {
                 av_free_packet(pkt);
                 return ret;
             }
         } else
             first = 0;
         frame_size = AV_RL32(pkt->data + pkt->size - 8);
         if (frame_size > INT_MAX - 4) {
             av_log(s, AV_LOG_ERROR, "Too large chunk size: %d\n", frame_size);
             return AVERROR(EIO);
         }
         if (AV_RL32(pkt->data + pkt->size - 12) == MKTAG('E', 'O', 'F', 'R')) {
             if (frame_size) {
                 av_log(s, AV_LOG_WARNING, "skipping %d bytes of end-of-frame marker chunk\n",
                        frame_size);
                 avio_skip(pb, frame_size);
             }
             return 0;
         }
         ret = av_append_packet(pb, pkt, frame_size);
         if (ret < 0) {
             av_free_packet(pkt);
             return ret;
         }
     }
 
     return 0;
 }
 
 AVInputFormat ff_dfa_demuxer = {
     "dfa",
     NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
     0,
     dfa_probe,
     dfa_read_header,
     dfa_read_packet,
     .flags = AVFMT_GENERIC_INDEX,
 };